Arrangement for the generation of intensive short-wave radiation based on a plasma

ABSTRACT

The invention is directed to an arrangement for generating intensive radiation based on a plasma, particularly short-wavelength radiation from soft x-ray radiation to extreme ultraviolet (EUV) radiation. The object of the invention is to find a novel possibility for generating radiation generated from plasma in which the individual pulse energy coupled into the plasma and, therefore, the usable radiation output are appreciably increased while retaining the advantages of mass-limited targets. According to the invention, this object is met in that the target generator has a multiple-channel nozzle with a plurality of separate orifices, wherein the orifices generate a plurality of target jets, the excitation radiation for generating plasma being directed simultaneously portion by portion to the target jets.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority of German application Serial No.103 06 668.3, filed Feb. 13, 2003, the complete disclosure of which ishereby incorporated by reference.

BACKGROUND OF THE INVENTION

[0002] a) Field of the Invention

[0003] The invention is directed to an arrangement for the generation ofintensive short-wavelength radiation based on a plasma, whereinhigh-energy excitation radiation is directed to a target flow in thevacuum chamber and, by means of a defined pulse energy, completelytransforms portions of the target flow into a dense, hot plasma whichemits particularly short-wavelength radiation in the extreme ultraviolet(EUV) range, i.e., in the wavelength region of 1 nm to 20 nm.

[0004] b) Description of the Related Art

[0005] The invention is used as a light source of short-wavelengthradiation, preferably for EUV lithography in the production ofintegrated circuits. However, it can also be used for incoherent lightsources in other spectral regions from the soft x-ray region to theinfrared spectral region.

[0006] In order to produce increasingly faster integrated circuits, itis necessary for the width of the individual structure on the chip to beincreasingly smaller. Since the resolution in optical methods (opticallithography) is proportional to the wavelength of the light that isused, development is toward increasingly smaller wavelengths. An areawith very good prospects for the future is EUV lithography (wavelengtharound 13.5 nm).

[0007] In the interest of economy, a determined throughput of wafersmust be ensured, which necessitates a light source having a high minimumoutput at a defined efficiency of the imaging optics. At the presenttime, there are no light sources in the wavelength region around 13.5 nmthat would be capable of providing the required outputs. Also, theselection of light sources which could potentially be capable of this isvery limited.

[0008] Based on the present state of knowledge, laser-produced plasmas,discharge plasmas and synchrotrons are the most promising radiationsources for EUV lithography. Sources based on a plasma have theadvantage that they can be incorporated relatively easily in existingproduction processes.

[0009] “Mass-limited” targets were developed in order to limit unwantedparticle emission in laser-produced plasmas which could sharply reducethe life of the plasma facing optics in particular. These mass-limitedtargets substantially reduce the amount of debris produced. In thisconnection, mass-limited means that the available target material iscompletely transformed into plasma by interaction with the energy beam.Since the amount of material available for generating radiation istherefore limited, the amount of energy in the beam pulse is exactlythat amount needed for optimal conversion of, e.g., laser photons intoEUV photons. Accordingly, at a given pulse repetition rate of the energybeam, the average output that can be coupled in is fixed and, at adetermined conversion efficiency, so also is the maximum EUV output thatcan be generated. The maximum pulse repetition rate of the energy beamis given in that the target is disturbed through the plasma generation,and a minimum time interval between the individual laser pulses whichdepends on the transport speed of the target flow is thereforenecessary.

[0010] Target concepts that have already been suggested include:

[0011] a continuous material jet (target jet) comprising, e.g.,condensed xenon (e.g., according to WO 97/40650 A1);

[0012] a dense droplet mist comprising microscopically small droplets(e.g., WO 01/30122 A1);

[0013] cluster targets (e.g., U.S. Pat. No. 5,577,092);

[0014] macroscopic droplets (e.g., EP 0 186 491 B1); and

[0015] ice crystals through the use of a spray (U.S. Pat. No.6,324,256).

[0016] In all of the known target concepts, the amount of materialavailable for an excitation pulse is small, so that the maximum energyof the individual pulse is limited. The transport speed of the targetmaterial and the diameter of the target jet can also not be increased toan unlimited extent for physical reasons (hydrodynamics), so that thepulse repetition rate of the energy beam is limited also. Since theaverage output is given by the product of individual pulse energy andrepetition rate of the excitation signal, there is an upper limit forthe EUV output that can be generated. Accordingly, with conventionaltargets it is not possible to reach the high average outputs in the EUVspectral region that are required by the semiconductor industry.

OBJECT AND SUMMARY OF THE INVENTION

[0017] It is the primary object of the invention to find a novelpossibility for generating radiation generated from plasma, particularlyEUV radiation, in which the individual pulse energy coupled into theplasma and, therefore, the usable radiation output are appreciablyincreased while retaining the advantages of mass-limited targets.

[0018] In an arrangement for generating intensive radiation based onplasma, containing a target generator with a nozzle for metering andorientation of a target flow for plasma generation and a vacuum chamber,wherein a high-energy excitation radiation is directed to the targetflow in the vacuum chamber and the target flow is completely convertedpiece by piece by means of a defined pulse energy of the excitationradiation into a plasma having a high conversion efficiency for theintensive radiation in a desired wavelength range, the above-statedobject is met according to the invention in that the nozzle of thetarget generator is a multiple-channel nozzle with a plurality ofseparate orifices, wherein the orifices generate a plurality of targetjets, the excitation radiation for generating plasma being directedsimultaneously portion by portion to the target jets.

[0019] The individual orifices of the nozzle are advantageously arrangedin such a way that a radiation spot focused by the excitation radiationon all of the target jets exiting the nozzle is covered spatiallyessentially uniformly by parallel target jets, all of the target jetsbeing completely irradiated over their diameter.

[0020] The individual orifices of the nozzle can advisably be arrangedin at least one row.

[0021] It is particularly advantageous with respect to minimizing thecoupling losses of the excitation radiation that the individual orificesof the nozzle are arranged in such a way that the target jets fill upthe radiation spot of the excitation radiation without gaps and withoutoverlapping, wherein the orifices of the nozzle are arranged so as to beoffset to the direction of the excitation radiation for target jetsappearing adjacent to one another in the radiation spot.

[0022] For this purpose, the individual orifices of the nozzle arepreferably arranged along a straight line which encloses an anglebetween 45° and 90° with the incident direction of the excitationradiation.

[0023] In another advantageous construction, the individual orifices ofthe nozzle are arranged in a plurality of rows at an offset to oneanother. In this connection, the orifices can advisably be provided asparallel rows with an equal spacing between the orifices in the nozzle,wherein the rows lie one behind the other with respect to the incidentdirection of the excitation radiation and are arranged so as to beoffset relative to one another by a fraction of the spacing between theorifices depending upon the quantity of rows arranged one behind theother. The orifices of the nozzle are preferably arranged in twoparallel rows which are oriented orthogonal to the direction of theexcitation radiation and are offset relative to one another by one halfof the orifice spacing.

[0024] In another suitable construction, the rows of orifices intersect,and intersecting rows share their first or last orifice as a commonorifice representing the intersection point and are oriented in amirror-symmetric manner relative to the incident direction of theexcitation radiation at the same angle of intersection.

[0025] It is particularly advisable that two intersecting rows oforifices are oriented in a V-shaped manner relative to the incidentdirection of the excitation radiation. The V-shape can be oriented withthe tip in the incident direction of the excitation radiation or withthe opening in the incident direction of the excitation radiation.

[0026] An energy beam pulsed in a desired manner is advantageouslyprovided as excitation radiation for the energy input into the targetjets, wherein the energy beam has a focus whose cross-sectional areacovers the width of all adjacent target jets simultaneously. The energybeam is preferably generated by a pulsed laser. However, a particlebeam, particularly an electron beam or ion beam, can also be used in asuitable manner. An energy beam in the form of a laser beam is advisablyfocused through cylindrical optics on the target jets on a focus linewhich is oriented orthogonal to the direction of the target jets.

[0027] In another constructional variant, the energy beam can also becomposed of a plurality of individual energy beams which are arranged ina row orthogonal to the direction of the target jets to aquasi-continuous focus line by suitable optical elements and strike thetarget jets simultaneously.

[0028] In another advisable arrangement for plasma excitation, theenergy beam is composed of a plurality of individual energy beams, eachof which is focused on a target jet and all target jets are irradiatedsimultaneously. A laser with beam-splitting optical elements or aplurality of synchronously operated lasers can be used for generatingthe row of individual energy beams.

[0029] In each of the excitation variants mentioned above, the energybeam is advisably optimized with respect to the efficiency with which itcouples energy into the plasma through the use of double pulsescomprising a pre-pulse and a main pulse or multiple pulses.

[0030] In the area of the interaction with the excitation beam, thetarget jets proceeding from the orifices of the multiple-channel nozzleare preferably continuous liquid jets, liquid jets which fall in dropletform at the latest in the area of interaction with the excitationradiation, or jets which pass into the solid aggregate state whenexiting from the nozzle into the vacuum chamber.

[0031] The target jets are preferably generated from condensed xenon.However, target jets comprising an aqueous solution of metallic saltsare also suitable.

[0032] The arrangement for generating plasma-generated radiation isadvantageously used as a radiation source in the wavelength regionsbetween soft x-ray radiation and the infrared spectral region. It ispreferably used for the generation of EUV radiation in the wavelengthregion between 1 nm and 20 nm for devices for semiconductor lithography,particularly for EUV lithography, in the region of 13.5 nm.

[0033] The invention proceeds from the basic idea that particularly theradiation outputs from a plasma-based radiation which are required insemiconductor lithography can not be achieved with conventional targetpreparation because of the mass limitation of the targets and because ofthe necessary target tracking (target flow). Since the quantity ofmaterial that is available for generating radiation after leaving thenozzle is limited and the target size can not be increased to any extentdesired, only a limited amount of energy of the excitation radiation canat best be coupled into the plasma emitting the desired radiation.

[0034] This seemingly insurmountable barrier of limited energyconversion is overcome, according to the invention, through theconstruction of a nozzle with a plurality of individual orifices in thatthe efficiency with which the excitation energy is coupled into plasmais increased and transmission losses are minimized at the same time. Thenozzle contains a plurality of channels which serve to generate aplurality of individual target jets in an interaction chamber (vacuumchamber) and to irradiate the individual jets simultaneously withhigh-energy excitation radiation (e.g., laser beam, electron beam, etc.)in order to generate a spatially expanded, homogeneous plasma.

[0035] With the arrangement according to the invention, it is possibleto generate radiation, particularly EUV radiation, generated from plasmawith a high average output, wherein the individual pulse energy that canbe coupled into the plasma and, therefore, the usable radiation outputare appreciably increased in spite of the mass limitation of the target.

[0036] The invention will be described more fully in the following withreference to embodiment examples.

BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In the drawings:

[0038]FIG. 1 shows the basic construction of the arrangement accordingto the invention with a multiple-channel nozzle for generating aplurality of parallel target jets which are spatially offset withrespect to the excitation beam and which are arranged on gaps;

[0039]FIGS. 2a-d are four top views of the multiple-channel nozzlesaccording to the invention for generating parallel target jets which arearranged one behind the other on gaps so as to be offset relative to oneanother with respect to the direction of the excitation radiation andwhich enable greater distances between the channels inside the nozzlewith minimal transmission loss of excitation radiation;

[0040]FIG. 3 shows a perspective view of a multiple-channel nozzle witha plurality of rows of orifices which are arranged so as to be offsetrelative to one another and in which all target jets are excited by anenergy beam having a large diameter;

[0041]FIG. 4 is a top view of the exit side of a multiple-channel nozzleaccording to the invention with a plurality of parallel rows of orifices(channels) in which an exciting energy beam (analogous to FIG. 3) makesit possible to irradiate all of the target jets in rows arranged fartherbehind on another through the spacing between the target jets;

[0042]FIG. 5 is a perspective view of a multiple-channel nozzle withchannels arranged in two rows so as to be offset relative to oneanother, wherein the target jets are excited by a plurality of laserbeams which are combined to form a line-shaped illumination;

[0043]FIG. 6 shows a perspective view of a multiple-channel nozzle withonly one linear arrangement of target jets in which laser beams whichare arranged next to one another in rows are focused on a target jet;

[0044]FIG. 7 is a perspective view of a multiple-channel nozzle withchannels arranged in two rows so as to be offset relative to oneanother, wherein the target jets are excited by a line-shapedillumination of a laser beam which is shaped via cylindrical optics; and

[0045]FIG. 8 is a perspective view of a multiple-channel nozzle withonly one row of nozzle orifices, wherein the line-shaped arrangement oftarget jets fill the excitation spot by rotating relative to the normalplane 48 to the excitation radiation (large-diameter laser beam) withoutgaps.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0046] In its basic variant, the arrangement according to the inventioncomprises a vacuum chamber 1, a target generator 2 which generates abundle of parallel target jets 3 by means of a nozzle 21 having aplurality of individual orifices 22, and an excitation radiation source4 which is focused orthogonally on the target jets 3 and forms aradiation spot 41 over all of the target jets 3.

[0047] The target jets 3 enter the vacuum chamber 1 through theindividual orifices 22 of the nozzle 21. In the vacuum chamber 1, theyare converted into plasma by bombardment with high-energy excitationradiation from the radiation source 1 which delivers an energy beam 42(laser beam, electron beam or ion beam) and irradiates all of the targetjets 3 simultaneously. The plasma emits light in the relevant spectralregion, preferably in the extreme violet (EUV) region.

[0048] The target jets 3 are liquid when they enter the vacuum chamber1, but can be liquid, continuous bet), discontinuous (droplet flow) orsolid (frozen) in the area of interaction with the energy beam 42. Onepossibility consists in using liquefied gases, preferably xenon forgenerating EUV. Other possible target materials are metallic salts inaqueous solution. Solid target jets 3 are generated by suitably cooledtarget material in that the target jets are frozen when entering thevacuum chamber 1 and are brought in this state into the area ofinteraction with the energy beam. The amount of target materialavailable for an individual pulse of the energy beam 42 and, therefore,the optimal individual pulse energy for the generation of EUV radiationis higher by a factor corresponding to the quantity of individualorifices 22 of the nozzle 21 at the identical exit speed of the targetmaterial and identical diameter of the individual orifices 22 comparedto a conventional single-channel nozzle. In this example, the orifices22 are arranged in such a way that the transmission losses for theincident energy beam 42 are minimal, i.e., the entire focused radiationspot 41 is completely covered by the target jets 3 arranged on gaps.This can be achieved, e.g., in that the individual orifices are arrangedso as to be spatially offset.

[0049] In principle, a kind of “watering can nozzle” with orifices 22arranged in a defined manner is used according to the invention.However, its peculiarity consists in that there are no nozzle orifices22 which are arranged one behind the other or which substantiallyoverlap in the direction of the energy beam 42. Due to the expansion ofthe diameters of the target jets 3 during conversion into plasma, evensmall gaps can remain between the target jets 3 in the projection of theradiation spot 41 of the energy beam 42.

[0050]FIG. 2 shows four essential variants of the arrangement oforifices 22 of the nozzle 21 in partial views a to d.

[0051]FIG. 2a is a top view showing a pattern of orifices 22 as anarrangement of two parallel rows 23 which are offset relative to oneanother by half of the spacing of the orifices 22 within each row 23.With three parallel rows 23, the offset would be decreased to a third ofthe spacing of the orifices 22 as will be described more fully in thefollowing with reference to FIG. 4.

[0052] In another variant according to FIG. 2b, two rows 23 are arrangedat opposite angles to the incident direction 43 of the energy beam 42.The two rows 23 share an orifice 22 of the nozzle 21, and theintersection 24 of the two rows 23 is given by this orifice 22 at thesame time. The angle relative to the incident direction 43 of the energybeam 42 is identical in terms of amount for both rows 23 and variesdepending on the diameter of the orifices 22 and a (possiblyintentional) gap formation or slight overlapping of the exiting targetjets 3 in the projection of the radiation spot 41 (as is shown in FIG.1). The pattern of orifices 22 corresponds to a V-shape which can beoriented with the intersection 24 of the rows 23 (i.e., with the tip ofthe V) in the direction of the energy beam 42 as is shown in FIG. 2b orcan be oriented opposite to the incident energy beam 42.

[0053]FIG. 2c shows a possibility in which the orifices 22 are arrangedin only one row 23. In order to avoid gaps between the target jets 3,the row 23 is inclined by an angle relative to the incident direction 43of the energy beam 42 according to the same criteria as in FIG. 2b. Incase gaps between the target jets 3 are permissible or desirable (see,e.g., the statements referring to FIG. 6), the angle can be very largeor exactly 90°. Otherwise, the selected angle is preferably around 45°.

[0054] Finally, without implying any lack of further possibilities, FIG.2d shows a combination of the nozzle patterns from FIG. 2a and FIG. 2b.This arrangement can be described as parallel rows 23 arranged onebehind the other with different distances between the orifices 22 oralso as V-shapes which continue transverse to the energy beam 42. Inessence, however, the pattern is more accurately described as a zigzagpattern oriented transverse to the incident direction 43 of the energybeam 42. Here, two parallel families 25 and 26 of orifices 22 arrangedin the direction opposite to the incident direction 43 of the energybeam 42 intersect, and the intersection points 24 are shared orifices 22as was already described with respect to the V-shape.

[0055] One possibility for coupling energy into the target consists inthat the target jets 3 generated by the multiple-channel nozzle 21 areirradiated by a laser as energy beam 42 in such a way that the radiationspot 41 corresponding to the laser focus (also often called the laserwaist) is at least as large as the width of the entire bundle of targetjets 3 (shown in FIG. 3).

[0056] In a case such as that described above, FIG. 4 shows the top viewof a nozzle 21 with three parallel rows 23 of orifices 22 arranged onebehind the other and the impinging light cone 44, shown schematically,of the laser waist as focused part of the energy beam 42.

[0057] As is clearly shown, the rows 23 are each displaced in a parallelmanner by about one third of the (uniform) distance between the orifices22 without overlapping of the target jets 3 exiting therefrom in thelight cone 44. However, due to the expansion of the diameters of thetarget jets 3 when converted into plasma, small gaps can also remainbetween the target jets 3 in the projection of the radiation spot 41 ofthe energy beam 42. This ensures that all of the target jets 3 receivethe same radiation output of the energy beam 42 and are accordinglyoptimally excited and can be converted into plasma.

[0058] Strictly speaking, the excitation of the target jets 3 isquasi-simultaneous because the target jets 3 from the rear rows 23 ofnozzle orifices 22 are actually reached later by the pulse of the energybeam 42 in the propagation direction of the energy beam 42. However,this may be ignored as it relates to plasma generation and will bedescribed as simultaneous hereinafter.

[0059] The plasmas (not shown) generated from the target jets 3 merge asa result of the simultaneous excitation of all target jets 3 into oneextended plasma with multiplied radiation power (corresponding to thequantity of target jets 3) in the desired wavelength region (e.g., EUVradiation) if other known factors of the energy input (radiation powerper target mass, optimized excitation through suitable temporal pulseshape, etc.) for the individual mass-limited target jets 3 are chosen.

[0060] In FIG. 5, the radiation spot 41 for the plasma generation in theentire bundle of target jets 3 is generated by spatial multiplexing inwhich the excitation radiation comprises a plurality of individual beams45 in a linear row arrangement 46 which are combined from a plurality ofidentical lasers or, through beam splitting, from one to a few lasersand bombard the target synchronously with respect to time. This has theadvantage that the pulse energy of the individual laser does not need tobe as high as in the case of a laser with a large diameter of thefocused radiation spot 41. As a result, the foci of the individual beams45 are arranged one above the other spatially and form a type of linefocus 47.

[0061] On the other hand, adjacent focusing of individual beams 45 oflasers is also worthy of consideration insofar as—corresponding to theview in FIG. 6—every target jet 3 is struck by exactly one individualbeam 45, so that the arrangement of target jets 3 without gaps is lesscritical in the design of the nozzle 21 and the orifices 22 can bearranged in only one row. This is important particularly forapplications in which the character of a point light source should notbe dispensed with for the resulting radiation. In this case, the desiredradiation should be coupled out of the plasma orthogonal to thedirection of the target jets 3 and to the incident direction 43 of theindividual beams 45. Consequently, the transmission losses andaccordingly also the in-coupling losses for an individual row 23 oforifices 22 in the nozzle 21 can be minimized in that the individualtarget jets 3 are irradiated synchronously by a respective individualbeam 45 (of a laser).

[0062] In addition, the coupling of energy into the target is improvedin that a smaller pre-pulse is radiated into the target jets 3 prior intime to the main energy pulse, so that a so-called pre-plasma is“smeared” over the width of the target jets 3 which are arranged at adistance from one another. The energy of the main pulse can be coupledinto this pre-plasma very effectively, so that the transmission lossesof excitation radiation are minimized in spite of the use of individualtarget jets 3 and the generation of radiation from the plasma isextensively homogeneous.

[0063] As can be seen from the view according to FIG. 7, it is likewisepossible and useful to employ a true line focus 47 for the irradiationof the target jets 3. The line focus 47 can be generated during laserexcitation, e.g., simply by means of cylindrical optics. A line focus 47of this kind, particularly for large-area bundles of target jets 3resulting in large-area plasma, can have considerable importance whenthe homogeneity of the plasma is important for generation of radiation,since a uniform energy input into each target jet 3 is carried out inthis configuration.

[0064]FIG. 8 shows yet another variant of the arrangement of target jets3 using a nozzle 21, according to FIG. 2c, in which there are notransmission losses of excitation radiation in an individual energy beam42. Although there is only a single row 23 of orifices 22 of the nozzle21 and the row 23 between the orifices 22 must compulsorily have spaces,the absence of gaps in the bundle of target jets 3 is brought about inthis case in that the row 23 of nozzle orifices 22 encloses an angle awith the normal plane 48 of the incident energy beam 42, so that thespacing present per se between the orifices 22 of the nozzle 21 does notappear in the projection of the radiation spot 41 of the excitationradiation on the bundle of target jets 3 that is rotated in this manner.Therefore, through selection of the angle a, the transmission losses canbe minimized in a suitable manner or the area-dependent coupling in ofenergy can be adjusted to a maximum. Further, as an added advantage, alarger area of the radiating plasma results also orthogonal to thedirections of the target jets 3 and energy beam 42.

[0065] Other design variants of the invention (particularly with respectto the nozzle variations according to FIGS. 2a to 2 d) are readilypossible without departing from the framework of this invention. Theexamples described above were based on parallel target jets 3 which arearranged without gaps and which enable relatively large target masseswhile retaining mass limitation. Further, other possible configurationswith intersecting or overlapping target jets or a plurality of bundlesof target jets 3 from variously positioned nozzles are not outside thescope of the invention. In particular, nozzle shapes and targetarrangements which are not shown or described explicitly in the drawingsare also to be considered as clearly belonging to the teaching accordingto the invention provided that they rely on the principle ofmultiplication of the radiation yield through the use of a plurality ofmass-limited targets and the synchronous excitation thereof withoutinventive activity.

[0066] While the foregoing description and drawings represent thepresent invention, it will be obvious to those skilled in the art thatvarious changes may be made therein without departing from the truespirit and scope of the present invention.

Reference Numbers

[0067]1 vacuum chamber

[0068]2 target generator

[0069]21 nozzle

[0070]22 orifices

[0071]23 row

[0072]24 intersection

[0073]25, 26 parallel families

[0074]3 target jets

[0075]4 excitation radiation source

[0076]41 focused radiation spot (of the excitation radiation)

[0077]42 energy beam

[0078]43 incident direction

[0079]44 light cone

[0080]45 individual beam (of the excitation radiation)

[0081]46 linear arrangement (of the individual beam foci)

[0082]47 line focus

[0083]48 normal plane (of the energy beam)

What is claimed is:
 1. An arrangement for generating intensive radiationbased on a plasma, comprising: a target generator with a nozzle formetering and orientation of a target flow for plasma generation; avacuum chamber; and a high-energy excitation radiation being directed tothe target flow in the vacuum chamber and the target flow beingcompletely converted piece by piece by a defined pulse energy of theexcitation radiation into a plasma having a high conversion efficiencyfor the intensive radiation in a desired wavelength region; said nozzleof the target generator being a multiple-channel nozzle with a pluralityof separate orifices, the orifices generating a plurality of targetjets, the excitation radiation for generating plasma being directedsimultaneously portion by portion to the target jets.
 2. The arrangementaccording to claim 1, wherein the individual orifices of the nozzle arearranged in such a way that a radiation spot focused by the excitationradiation on all of the target jets exiting the nozzle is coveredspatially essentially uniformly by parallel target jets, all of thetarget jets being completely irradiated over their diameter.
 3. Thearrangement according to claim 2, wherein the individual orifices of thenozzle are arranged in at least one row.
 4. The arrangement according toclaim 2, wherein the individual orifices of the nozzle are arranged insuch a way that the target jets fill the radiation spot of theexcitation radiation without gaps and without overlapping, wherein theorifices of the nozzle are arranged so as to be offset to the directionof the excitation radiation for target jets appearing adjacent to oneanother in the radiation spot.
 5. The arrangement according to claim 2,wherein the individual orifices of the nozzle are arranged in a row,wherein the row of orifices encloses an angle between 45° and 90° withthe incident direction of the excitation radiation.
 6. The arrangementaccording to claim 4, wherein the individual orifices of the nozzle arearranged in a plurality of rows so as to be offset to one another. 7.The arrangement according to claim 6, wherein the orifices are providedas parallel rows with an equal spacing between the orifices in thenozzle, wherein the rows are arranged one behind the other with respectto the incident direction of the excitation radiation and are arrangedso as to be offset relative to one another by a fraction of the spacingbetween the orifices depending upon the quantity of rows arranged onebehind the other.
 8. The arrangement according to claim 7, wherein theorifices of the nozzle are arranged in two parallel rows which areoriented orthogonal to the direction of the excitation radiation and areoffset relative to one another by one half of the orifice spacing. 9.The arrangement according to claim 6, wherein the rows of orificesintersect, and intersecting rows share their first or last orifice as acommon intersection and are oriented in a mirror-symmetric mannerrelative to the incident direction of the excitation radiation at thesame angle of intersection.
 10. The arrangement according to claim 9,wherein two intersecting rows of orifices are oriented in a V-shapedmanner relative to the incident direction of the excitation radiation.11. The arrangement according to claim 10, wherein the V-shape isoriented with the tip in the incident direction of the excitationradiation.
 12. The arrangement according to claim 10, wherein theV-shape is oriented with the opening opposite to the incident directionof the excitation radiation.
 13. The arrangement according to claim 1,wherein a pulsed energy beam is provided as excitation radiation,wherein the energy beam has a focus whose cross-sectional area coversthe width of all adjacent target jets simultaneously.
 14. Thearrangement according to claim 13, wherein the energy beam is generatedby a pulsed laser.
 15. The arrangement according to claim 13, whereinthe energy beam is a particle beam, particularly an electron beam. 16.The arrangement according to claim 13, wherein the energy beam is aparticle beam, particularly an ion beam.
 17. The arrangement accordingto claim 13, wherein the energy beam is focused through suitable opticson the target jets on a focus line which is oriented orthogonal to thedirection of the target jets.
 18. The arrangement according to claim 13,wherein the energy beam is composed of a plurality of individual energybeams, wherein the energy beams are arranged in a row orthogonal to thedirection of the target jets to a quasi-continuous focus line bysuitable optical elements and strike the target jets simultaneously. 19.The arrangement according to claim 13, wherein the energy beam iscomposed of a plurality of individual energy beams, wherein each of theindividual energy beams is focused on a target jet and all target jetsare irradiated simultaneously.
 20. The arrangement according to claim18, wherein a laser with beam-splitting optical elements is provided forgenerating the row of individual energy beams.
 21. The arrangementaccording to claim 18, wherein a plurality of synchronously operatedlasers is provided for generating the row of individual energy beams.22. The arrangement according to claim 13, wherein the energy beam isoptimized with respect to the efficiency with which it couples in energythrough the use of multiple pulses, particularly double pulses,comprising a pre-pulse and a main pulse.
 23. The arrangement accordingto claim 1, wherein the target jets proceeding from the orifices of themultiple-channel nozzle are continuous jets in the area of theinteraction with the excitation radiation.
 24. The arrangement accordingto claim 1, wherein the target jets proceeding from the orifices of themultiple-channel nozzle fall in drops at the latest in the area ofinteraction with the excitation radiation.
 25. The arrangement accordingto claim 1, wherein the target jets are liquid jets.
 26. The arrangementaccording to claim 1, wherein the target jets are frozen solid jets whenexiting from the nozzle into the vacuum chamber.
 27. The arrangementaccording to claim 23, wherein the target jets are generated fromcondensed xenon.
 28. The arrangement according to claim 23, wherein thetarget jets are generated from aqueous solution of metallic salts.
 29. Amethod for using the arrangement according to claim 1, comprising thestep of generating plasma-generated radiation in the wavelength regionsbetween soft x-ray radiation and the infrared spectral region.
 30. Amethod for using the arrangement according to claim 1, comprising thestep of generating EUV radiation in the wavelength region between 1 nmand 20 nm for devices for semiconductor lithography, particularly forEUV lithography in the region of 13.5 nm.